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path: root/drivers/md/bcache/sysfs.c
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2024-06-25bcache: remove heap-related macros and switch to generic min_heapKuan-Wei Chiu1-1/+3
Drop the heap-related macros from bcache and replacing them with the generic min_heap implementation from include/linux. By doing so, code readability is improved by using functions instead of macros. Moreover, the min_heap implementation in include/linux adopts a bottom-up variation compared to the textbook version currently used in bcache. This bottom-up variation allows for approximately 50% reduction in the number of comparison operations during heap siftdown, without changing the number of swaps, thus making it more efficient. Link: https://lkml.kernel.org/ioyfizrzq7w7mjrqcadtzsfgpuntowtjdw5pgn4qhvsdp4mqqg@nrlek5vmisbu Link: https://lkml.kernel.org/r/20240524152958.919343-16-visitorckw@gmail.com Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com> Reviewed-by: Ian Rogers <irogers@google.com> Acked-by: Coly Li <colyli@suse.de> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Bagas Sanjaya <bagasdotme@gmail.com> Cc: Brian Foster <bfoster@redhat.com> Cc: Ching-Chun (Jim) Huang <jserv@ccns.ncku.edu.tw> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Sakai <msakai@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-09bcache: fix variable length array abuse in btree_iterMatthew Mirvish1-1/+1
btree_iter is used in two ways: either allocated on the stack with a fixed size MAX_BSETS, or from a mempool with a dynamic size based on the specific cache set. Previously, the struct had a fixed-length array of size MAX_BSETS which was indexed out-of-bounds for the dynamically-sized iterators, which causes UBSAN to complain. This patch uses the same approach as in bcachefs's sort_iter and splits the iterator into a btree_iter with a flexible array member and a btree_iter_stack which embeds a btree_iter as well as a fixed-length data array. Cc: stable@vger.kernel.org Closes: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2039368 Signed-off-by: Matthew Mirvish <matthew@mm12.xyz> Signed-off-by: Coly Li <colyli@suse.de> Link: https://lore.kernel.org/r/20240509011117.2697-3-colyli@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-23bcache: use of hlist_count_nodes()Pierre Gondois1-7/+1
Make use of the newly added hlist_count_nodes(). Link: https://lkml.kernel.org/r/20240104164937.424320-4-pierre.gondois@arm.com Signed-off-by: Pierre Gondois <pierre.gondois@arm.com> Acked-by: Coly Li <colyli@suse.de> Acked-by: Marco Elver <elver@google.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Arve Hjønnevåg <arve@android.com> Cc: Carlos Llamas <cmllamas@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jani Nikula <jani.nikula@intel.com> Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Cc: Kees Cook <keescook@chromium.org> Cc: Kent Overstreet <kent.overstreet@gmail.com> Cc: Martijn Coenen <maco@android.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Todd Kjos <tkjos@android.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-11-20bcache: prevent potential division by zero errorRand Deeb1-1/+1
In SHOW(), the variable 'n' is of type 'size_t.' While there is a conditional check to verify that 'n' is not equal to zero before executing the 'do_div' macro, concerns arise regarding potential division by zero error in 64-bit environments. The concern arises when 'n' is 64 bits in size, greater than zero, and the lower 32 bits of it are zeros. In such cases, the conditional check passes because 'n' is non-zero, but the 'do_div' macro casts 'n' to 'uint32_t,' effectively truncating it to its lower 32 bits. Consequently, the 'n' value becomes zero. To fix this potential division by zero error and ensure precise division handling, this commit replaces the 'do_div' macro with div64_u64(). div64_u64() is designed to work with 64-bit operands, guaranteeing that division is performed correctly. This change enhances the robustness of the code, ensuring that division operations yield accurate results in all scenarios, eliminating the possibility of division by zero, and improving compatibility across different 64-bit environments. Found by Linux Verification Center (linuxtesting.org) with SVACE. Signed-off-by: Rand Deeb <rand.sec96@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Coly Li <colyli@suse.de> Link: https://lore.kernel.org/r/20231120052503.6122-5-colyli@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-10-04bcache: dynamically allocate the md-bcache shrinkerQi Zheng1-1/+2
In preparation for implementing lockless slab shrink, use new APIs to dynamically allocate the md-bcache shrinker, so that it can be freed asynchronously via RCU. Then it doesn't need to wait for RCU read-side critical section when releasing the struct cache_set. Link: https://lkml.kernel.org/r/20230911094444.68966-27-zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Muchun Song <songmuchun@bytedance.com> Cc: Coly Li <colyli@suse.de> Cc: Kent Overstreet <kent.overstreet@gmail.com> Cc: Abhinav Kumar <quic_abhinavk@quicinc.com> Cc: Alasdair Kergon <agk@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Andreas Gruenbacher <agruenba@redhat.com> Cc: Anna Schumaker <anna@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bob Peterson <rpeterso@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Carlos Llamas <cmllamas@google.com> Cc: Chandan Babu R <chandan.babu@oracle.com> Cc: Chao Yu <chao@kernel.org> Cc: Chris Mason <clm@fb.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Christian Koenig <christian.koenig@amd.com> Cc: Chuck Lever <cel@kernel.org> Cc: Dai Ngo <Dai.Ngo@oracle.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Airlie <airlied@gmail.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Sterba <dsterba@suse.com> Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Cc: Gao Xiang <hsiangkao@linux.alibaba.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Huang Rui <ray.huang@amd.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Jason Wang <jasowang@redhat.com> Cc: Jeff Layton <jlayton@kernel.org> Cc: Jeffle Xu <jefflexu@linux.alibaba.com> Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Josef Bacik <josef@toxicpanda.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kirill Tkhai <tkhai@ya.ru> Cc: Marijn Suijten <marijn.suijten@somainline.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Mike Snitzer <snitzer@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nadav Amit <namit@vmware.com> Cc: Neil Brown <neilb@suse.de> Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Cc: Olga Kornievskaia <kolga@netapp.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rob Clark <robdclark@gmail.com> Cc: Rob Herring <robh@kernel.org> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Sean Paul <sean@poorly.run> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Song Liu <song@kernel.org> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Steven Price <steven.price@arm.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com> Cc: Tom Talpey <tom@talpey.com> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Cc: Yue Hu <huyue2@coolpad.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-15bcache: Convert to use sysfs_emit()/sysfs_emit_at() APIsye xingchen1-16/+15
Follow the advice of the Documentation/filesystems/sysfs.rst and show() should only use sysfs_emit() or sysfs_emit_at() when formatting the value to be returned to user space. Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn> Signed-off-by: Coly Li <colyli@suse.de> Link: https://lore.kernel.org/r/20230615121223.22502-2-colyli@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-04-18block: remove QUEUE_FLAG_DISCARDChristoph Hellwig1-1/+1
Just use a non-zero max_discard_sectors as an indicator for discard support, similar to what is done for write zeroes. The only places where needs special attention is the RAID5 driver, which must clear discard support for security reasons by default, even if the default stacking rules would allow for it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd] Acked-by: Jan Höppner <hoeppner@linux.ibm.com> [s390] Acked-by: Coly Li <colyli@suse.de> [bcache] Acked-by: David Sterba <dsterba@suse.com> [btrfs] Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220415045258.199825-25-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-01-26bcache: use default_groups in kobj_typeGreg Kroah-Hartman1-5/+10
There are currently 2 ways to create a set of sysfs files for a kobj_type, through the default_attrs field, and the default_groups field. Move the bcache sysfs code to use default_groups field which has been the preferred way since aa30f47cf666 ("kobject: Add support for default attribute groups to kobj_type") so that we can soon get rid of the obsolete default_attrs field. Cc: Kent Overstreet <kent.overstreet@gmail.com> Cc: linux-bcache@vger.kernel.org Acked-by: Coly Li <colyli@suse.de> Link: https://lore.kernel.org/r/20220106100004.3277439-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-20bcache: remove the backing_dev_name field from struct cached_devChristoph Hellwig1-1/+1
Just use the %pg format specifier to print the name directly. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Coly Li <colyli@suse.de> Link: https://lore.kernel.org/r/20211020143812.6403-7-colyli@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-09bcache: remove bcache device self-defined readaheadColy Li1-4/+0
For read cache missing, bcache defines a readahead size for the read I/O request to the backing device for the missing data. This readahead size is initialized to 0, and almost no one uses it to avoid unnecessary read amplifying onto backing device and write amplifying onto cache device. Considering upper layer file system code has readahead logic allready and works fine with readahead_cache_policy sysfile interface, we don't have to keep bcache self-defined readahead anymore. This patch removes the bcache self-defined readahead for cache missing request for backing device, and the readahead sysfs file interfaces are removed as well. This is the preparation for next patch to fix potential kernel panic due to oversized request in a simpler method. Reported-by: Alexander Ullrich <ealex1979@gmail.com> Reported-by: Diego Ercolani <diego.ercolani@gmail.com> Reported-by: Jan Szubiak <jan.szubiak@linuxpolska.pl> Reported-by: Marco Rebhan <me@dblsaiko.net> Reported-by: Matthias Ferdinand <bcache@mfedv.net> Reported-by: Victor Westerhuis <victor@westerhu.is> Reported-by: Vojtech Pavlik <vojtech@suse.cz> Reported-and-tested-by: Rolf Fokkens <rolf@rolffokkens.nl> Reported-and-tested-by: Thorsten Knabe <linux@thorsten-knabe.de> Signed-off-by: Coly Li <colyli@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: stable@vger.kernel.org Cc: Kent Overstreet <kent.overstreet@gmail.com> Cc: Nix <nix@esperi.org.uk> Cc: Takashi Iwai <tiwai@suse.com> Link: https://lore.kernel.org/r/20210607125052.21277-2-colyli@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-10bcache: Avoid comma separated statementsJoe Perches1-2/+4
Use semicolons and braces. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-10bcache: consider the fragmentation when update the writeback ratedongdong tao1-0/+23
Current way to calculate the writeback rate only considered the dirty sectors, this usually works fine when the fragmentation is not high, but it will give us unreasonable small rate when we are under a situation that very few dirty sectors consumed a lot dirty buckets. In some case, the dirty bucekts can reached to CUTOFF_WRITEBACK_SYNC while the dirty data(sectors) not even reached the writeback_percent, the writeback rate will still be the minimum value (4k), thus it will cause all the writes to be stucked in a non-writeback mode because of the slow writeback. We accelerate the rate in 3 stages with different aggressiveness, the first stage starts when dirty buckets percent reach above BCH_WRITEBACK_FRAGMENT_THRESHOLD_LOW (50), the second is BCH_WRITEBACK_FRAGMENT_THRESHOLD_MID (57), the third is BCH_WRITEBACK_FRAGMENT_THRESHOLD_HIGH (64). By default the first stage tries to writeback the amount of dirty data in one bucket (on average) in (1 / (dirty_buckets_percent - 50)) second, the second stage tries to writeback the amount of dirty data in one bucket in (1 / (dirty_buckets_percent - 57)) * 100 millisecond, the third stage tries to writeback the amount of dirty data in one bucket in (1 / (dirty_buckets_percent - 64)) millisecond. the initial rate at each stage can be controlled by 3 configurable parameters writeback_rate_fp_term_{low|mid|high}, they are by default 1, 10, 1000, the hint of IO throughput that these values are trying to achieve is described by above paragraph, the reason that I choose those value as default is based on the testing and the production data, below is some details: A. When it comes to the low stage, there is still a bit far from the 70 threshold, so we only want to give it a little bit push by setting the term to 1, it means the initial rate will be 170 if the fragment is 6, it is calculated by bucket_size/fragment, this rate is very small, but still much reasonable than the minimum 8. For a production bcache with unheavy workload, if the cache device is bigger than 1 TB, it may take hours to consume 1% buckets, so it is very possible to reclaim enough dirty buckets in this stage, thus to avoid entering the next stage. B. If the dirty buckets ratio didn't turn around during the first stage, it comes to the mid stage, then it is necessary for mid stage to be more aggressive than low stage, so i choose the initial rate to be 10 times more than low stage, that means 1700 as the initial rate if the fragment is 6. This is some normal rate we usually see for a normal workload when writeback happens because of writeback_percent. C. If the dirty buckets ratio didn't turn around during the low and mid stages, it comes to the third stage, and it is the last chance that we can turn around to avoid the horrible cutoff writeback sync issue, then we choose 100 times more aggressive than the mid stage, that means 170000 as the initial rate if the fragment is 6. This is also inferred from a production bcache, I've got one week's writeback rate data from a production bcache which has quite heavy workloads, again, the writeback is triggered by the writeback percent, the highest rate area is around 100000 to 240000, so I believe this kind aggressiveness at this stage is reasonable for production. And it should be mostly enough because the hint is trying to reclaim 1000 bucket per second, and from that heavy production env, it is consuming 50 bucket per second on average in one week's data. Option writeback_consider_fragment is to control whether we want this feature to be on or off, it's on by default. Lastly, below is the performance data for all the testing result, including the data from production env: https://docs.google.com/document/d/1AmbIEa_2MhB9bqhC3rfga9tp7n9YX9PLn0jSUxscVW0/edit?usp=sharing Signed-off-by: dongdong tao <dongdong.tao@canonical.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-23md/bcache: convert comma to semicolonZheng Yongjun1-1/+1
Replace a comma between expression statements by a semicolon. Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com> Signed-off-by: Coly Li <colyli@sue.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02bcache: check and set sync status on cache's in-memory super blockColy Li1-3/+3
Currently the cache's sync status is checked and set on cache set's in- memory partial super block. After removing the embedded struct cache_sb from cache set and reference cache's in-memory super block from struct cache_set, the sync status can set and check directly on cache's super block. This patch checks and sets the cache sync status directly on cache's in-memory super block. This is a preparation for later removing embedded struct cache_sb from struct cache_set. Signed-off-by: Coly Li <colyli@suse.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02bcache: only use bucket_bytes() on struct cacheColy Li1-1/+1
Because struct cache_set and struct cache both have struct cache_sb, macro bucket_bytes() currently are used on both of them. When removing the embedded struct cache_sb from struct cache_set, this macro won't be used on struct cache_set anymore. This patch unifies all bucket_bytes() usage only on struct cache, this is one of the preparation to remove the embedded struct cache_sb from struct cache_set. Signed-off-by: Coly Li <colyli@suse.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-02bcache: only use block_bytes() on struct cacheColy Li1-1/+1
Because struct cache_set and struct cache both have struct cache_sb, therefore macro block_bytes() can be used on both of them. When removing the embedded struct cache_sb from struct cache_set, this macro won't be used on struct cache_set anymore. This patch unifies all block_bytes() usage only on struct cache, this is one of the preparation to remove the embedded struct cache_sb from struct cache_set. Signed-off-by: Coly Li <colyli@suse.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-25bcache: add sysfs file to display feature sets information of cache setColy Li1-0/+14
The following three sysfs files are created to display according feature set information of bcache: /sys/fs/bcache/<cache set UUID>/internal/feature_compat /sys/fs/bcache/<cache set UUID>/internal/feature_ro_compat /sys/fs/bcache/<cache set UUID>/internal/feature_incompat is added by this patch, to display feature sets information of the cache set. Now only an incompat feature 'large_bucket' added in bcache, the sysfs file content is: [large_bucket] string large_bucket means the running bcache drive supports incompat feature 'large_bucket', the wrapping [] means the 'large_bucket' feature is currently enabled on this cache set. This patch is ready to display compat and ro_compat features, in future once bcache code implements such feature sets, the according feature strings will be displayed in their sysfs files too. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-27bcache: Convert pr_<level> uses to a more typical styleJoe Perches1-4/+4
Remove the trailing newline from the define of pr_fmt and add newlines to the uses. Miscellanea: o Convert bch_bkey_dump from multiple uses of pr_err to pr_cont as the earlier conversion was inappropriate done causing multiple lines to be emitted where only a single output line was desired o Use vsprintf extension %pV in bch_cache_set_error to avoid multiple line output where only a single line output was desired o Coalesce formats Fixes: 6ae63e3501c4 ("bcache: replace printk() by pr_*() routines") Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-22bcache: Use scnprintf() for avoiding potential buffer overflowTakashi Iwai1-1/+1
Since snprintf() returns the would-be-output size instead of the actual output size, the succeeding calls may go beyond the given buffer limit. Fix it by replacing with scnprintf(). Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-01bcache: add readahead cache policy options via sysfs interfaceColy Li1-0/+22
In year 2007 high performance SSD was still expensive, in order to save more space for real workload or meta data, the readahead I/Os for non-meta data was bypassed and not cached on SSD. In now days, SSD price drops a lot and people can find larger size SSD with more comfortable price. It is unncessary to alway bypass normal readahead I/Os to save SSD space for now. This patch adds options for readahead data cache policies via sysfs file /sys/block/bcache<N>/readahead_cache_policy, the options are, - "all": cache all readahead data I/Os. - "meta-only": only cache meta data, and bypass other regular I/Os. If users want to make bcache continue to only cache readahead request for metadata and bypass regular data readahead, please set "meta-only" to this sysfs file. By default, bcache will back to cache all read- ahead requests now. Cc: stable@vger.kernel.org Signed-off-by: Coly Li <colyli@suse.de> Acked-by: Eric Wheeler <bcache@linux.ewheeler.net> Cc: Michael Lyle <mlyle@lyle.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-14bcache: add idle_max_writeback_rate sysfs interfaceColy Li1-0/+7
For writeback mode, if there is no regular I/O request for a while, the writeback rate will be set to the maximum value (1TB/s for now). This is good for most of the storage workload, but there are still people don't what the maximum writeback rate in I/O idle time. This patch adds a sysfs interface file idle_max_writeback_rate to permit people to disable maximum writeback rate. Then the minimum writeback rate can be advised by writeback_rate_minimum in the bcache device's sysfs interface. Reported-by: Christian Balzer <chibi@gol.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-09-18Merge tag 'for-5.4/block-2019-09-16' of git://git.kernel.dk/linux-blockLinus Torvalds1-0/+1
Pull block updates from Jens Axboe: - Two NVMe pull requests: - ana log parse fix from Anton - nvme quirks support for Apple devices from Ben - fix missing bio completion tracing for multipath stack devices from Hannes and Mikhail - IP TOS settings for nvme rdma and tcp transports from Israel - rq_dma_dir cleanups from Israel - tracing for Get LBA Status command from Minwoo - Some nvme-tcp cleanups from Minwoo, Potnuri and Myself - Some consolidation between the fabrics transports for handling the CAP register - reset race with ns scanning fix for fabrics (move fabrics commands to a dedicated request queue with a different lifetime from the admin request queue)." - controller reset and namespace scan races fixes - nvme discovery log change uevent support - naming improvements from Keith - multiple discovery controllers reject fix from James - some regular cleanups from various people - Series fixing (and re-fixing) null_blk debug printing and nr_devices checks (André) - A few pull requests from Song, with fixes from Andy, Guoqing, Guilherme, Neil, Nigel, and Yufen. - REQ_OP_ZONE_RESET_ALL support (Chaitanya) - Bio merge handling unification (Christoph) - Pick default elevator correctly for devices with special needs (Damien) - Block stats fixes (Hou) - Timeout and support devices nbd fixes (Mike) - Series fixing races around elevator switching and device add/remove (Ming) - sed-opal cleanups (Revanth) - Per device weight support for BFQ (Fam) - Support for blk-iocost, a new model that can properly account cost of IO workloads. (Tejun) - blk-cgroup writeback fixes (Tejun) - paride queue init fixes (zhengbin) - blk_set_runtime_active() cleanup (Stanley) - Block segment mapping optimizations (Bart) - lightnvm fixes (Hans/Minwoo/YueHaibing) - Various little fixes and cleanups * tag 'for-5.4/block-2019-09-16' of git://git.kernel.dk/linux-block: (186 commits) null_blk: format pr_* logs with pr_fmt null_blk: match the type of parameter nr_devices null_blk: do not fail the module load with zero devices block: also check RQF_STATS in blk_mq_need_time_stamp() block: make rq sector size accessible for block stats bfq: Fix bfq linkage error raid5: use bio_end_sector in r5_next_bio raid5: remove STRIPE_OPS_REQ_PENDING md: add feature flag MD_FEATURE_RAID0_LAYOUT md/raid0: avoid RAID0 data corruption due to layout confusion. raid5: don't set STRIPE_HANDLE to stripe which is in batch list raid5: don't increment read_errors on EILSEQ return nvmet: fix a wrong error status returned in error log page nvme: send discovery log page change events to userspace nvme: add uevent variables for controller devices nvme: enable aen regardless of the presence of I/O queues nvme-fabrics: allow discovery subsystems accept a kato nvmet: Use PTR_ERR_OR_ZERO() in nvmet_init_discovery() nvme: Remove redundant assignment of cq vector nvme: Assign subsys instance from first ctrl ...
2019-09-03bcache: add cond_resched() in __bch_cache_cmp()Shile Zhang1-0/+1
Read /sys/fs/bcache/<uuid>/cacheN/priority_stats can take very long time with huge cache after long run. Signed-off-by: Shile Zhang <shile.zhang@linux.alibaba.com> Tested-by: Heitor Alves de Siqueira <halves@canonical.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-09bcache: Revert "bcache: use sysfs_match_string() instead of ↵Coly Li1-8/+12
__sysfs_match_string()" This reverts commit 89e0341af082dbc170019f908846f4a424efc86b. In drivers/md/bcache/sysfs.c:bch_snprint_string_list(), NULL pointer at the end of list is necessary. Remove the NULL from last element of each lists will cause the following panic, [ 4340.455652] bcache: register_cache() registered cache device nvme0n1 [ 4340.464603] bcache: register_bdev() registered backing device sdk [ 4421.587335] bcache: bch_cached_dev_run() cached dev sdk is running already [ 4421.587348] bcache: bch_cached_dev_attach() Caching sdk as bcache0 on set 354e1d46-d99f-4d8b-870b-078b80dc88a6 [ 5139.247950] general protection fault: 0000 [#1] SMP NOPTI [ 5139.247970] CPU: 9 PID: 5896 Comm: cat Not tainted 4.12.14-95.29-default #1 SLE12-SP4 [ 5139.247988] Hardware name: HPE ProLiant DL380 Gen10/ProLiant DL380 Gen10, BIOS U30 04/18/2019 [ 5139.248006] task: ffff888fb25c0b00 task.stack: ffff9bbacc704000 [ 5139.248021] RIP: 0010:string+0x21/0x70 [ 5139.248030] RSP: 0018:ffff9bbacc707bf0 EFLAGS: 00010286 [ 5139.248043] RAX: ffffffffa7e432e3 RBX: ffff8881c20da02a RCX: ffff0a00ffffff04 [ 5139.248058] RDX: 3f00656863616362 RSI: ffff8881c20db000 RDI: ffffffffffffffff [ 5139.248075] RBP: ffff8881c20db000 R08: 0000000000000000 R09: ffff8881c20da02a [ 5139.248090] R10: 0000000000000004 R11: 0000000000000000 R12: ffff9bbacc707c48 [ 5139.248104] R13: 0000000000000fd6 R14: ffffffffc0665855 R15: ffffffffc0665855 [ 5139.248119] FS: 00007faf253b8700(0000) GS:ffff88903f840000(0000) knlGS:0000000000000000 [ 5139.248137] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 5139.248149] CR2: 00007faf25395008 CR3: 0000000f72150006 CR4: 00000000007606e0 [ 5139.248164] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 5139.248179] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 5139.248193] PKRU: 55555554 [ 5139.248200] Call Trace: [ 5139.248210] vsnprintf+0x1fb/0x510 [ 5139.248221] snprintf+0x39/0x40 [ 5139.248238] bch_snprint_string_list.constprop.15+0x5b/0x90 [bcache] [ 5139.248256] __bch_cached_dev_show+0x44d/0x5f0 [bcache] [ 5139.248270] ? __alloc_pages_nodemask+0xb2/0x210 [ 5139.248284] bch_cached_dev_show+0x2c/0x50 [bcache] [ 5139.248297] sysfs_kf_seq_show+0xbb/0x190 [ 5139.248308] seq_read+0xfc/0x3c0 [ 5139.248317] __vfs_read+0x26/0x140 [ 5139.248327] vfs_read+0x87/0x130 [ 5139.248336] SyS_read+0x42/0x90 [ 5139.248346] do_syscall_64+0x74/0x160 [ 5139.248358] entry_SYSCALL_64_after_hwframe+0x3d/0xa2 [ 5139.248370] RIP: 0033:0x7faf24eea370 [ 5139.248379] RSP: 002b:00007fff82d03f38 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 5139.248395] RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007faf24eea370 [ 5139.248411] RDX: 0000000000020000 RSI: 00007faf25396000 RDI: 0000000000000003 [ 5139.248426] RBP: 00007faf25396000 R08: 00000000ffffffff R09: 0000000000000000 [ 5139.248441] R10: 000000007c9d4d41 R11: 0000000000000246 R12: 00007faf25396000 [ 5139.248456] R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000fff [ 5139.248892] Code: ff ff ff 0f 1f 80 00 00 00 00 49 89 f9 48 89 cf 48 c7 c0 e3 32 e4 a7 48 c1 ff 30 48 81 fa ff 0f 00 00 48 0f 46 d0 48 85 ff 74 45 <44> 0f b6 02 48 8d 42 01 45 84 c0 74 38 48 01 fa 4c 89 cf eb 0e The simplest way to fix is to revert commit 89e0341af082 ("bcache: use sysfs_match_string() instead of __sysfs_match_string()"). This bug was introduced in Linux v5.2, so this fix only applies to Linux v5.2 is enough for stable tree maintainer. Fixes: 89e0341af082 ("bcache: use sysfs_match_string() instead of __sysfs_match_string()") Cc: stable@vger.kernel.org Cc: Alexandru Ardelean <alexandru.ardelean@analog.com> Reported-by: Peifeng Lin <pflin@suse.com> Acked-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28bcache: add reclaimed_journal_buckets to struct cache_setColy Li1-0/+5
Now we have counters for how many times jouranl is reclaimed, how many times cached dirty btree nodes are flushed, but we don't know how many jouranl buckets are really reclaimed. This patch adds reclaimed_journal_buckets into struct cache_set, this is an increasing only counter, to tell how many journal buckets are reclaimed since cache set runs. From all these three counters (reclaim, reclaimed_journal_buckets, flush_write), we can have idea how well current journal space reclaim code works. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28bcache: remove retry_flush_write from struct cache_setColy Li1-5/+0
In struct cache_set, retry_flush_write is added for commit c4dc2497d50d ("bcache: fix high CPU occupancy during journal") which is reverted in previous patch. Now it is useless anymore, and this patch removes it from bcache code. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28bcache: avoid a deadlock in bcache_reboot()Coly Li1-0/+26
It is quite frequently to observe deadlock in bcache_reboot() happens and hang the system reboot process. The reason is, in bcache_reboot() when calling bch_cache_set_stop() and bcache_device_stop() the mutex bch_register_lock is held. But in the process to stop cache set and bcache device, bch_register_lock will be acquired again. If this mutex is held here, deadlock will happen inside the stopping process. The aftermath of the deadlock is, whole system reboot gets hung. The fix is to avoid holding bch_register_lock for the following loops in bcache_reboot(), list_for_each_entry_safe(c, tc, &bch_cache_sets, list) bch_cache_set_stop(c); list_for_each_entry_safe(dc, tdc, &uncached_devices, list) bcache_device_stop(&dc->disk); A module range variable 'bcache_is_reboot' is added, it sets to true in bcache_reboot(). In register_bcache(), if bcache_is_reboot is checked to be true, reject the registration by returning -EBUSY immediately. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28bcache: fix mistaken sysfs entry for io_error counterColy Li1-2/+2
In bch_cached_dev_files[] from driver/md/bcache/sysfs.c, sysfs_errors is incorrectly inserted in. The correct entry should be sysfs_io_errors. This patch fixes the problem and now I/O errors of cached device can be read from /sys/block/bcache<N>/bcache/io_errors. Fixes: c7b7bd07404c5 ("bcache: add io_disable to struct cached_dev") Signed-off-by: Coly Li <colyli@suse.de> Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28bcache: add return value check to bch_cached_dev_run()Coly Li1-2/+5
This patch adds return value check to bch_cached_dev_run(), now if there is error happens inside bch_cached_dev_run(), it can be catched. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28bcache: use sysfs_match_string() instead of __sysfs_match_string()Alexandru Ardelean1-12/+8
The arrays (of strings) that are passed to __sysfs_match_string() are static, so use sysfs_match_string() which does an implicit ARRAY_SIZE() over these arrays. Functionally, this doesn't change anything. The change is more cosmetic. It only shrinks the static arrays by 1 byte each. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-13bcache: only set BCACHE_DEV_WB_RUNNING when cached device attachedColy Li1-1/+6
When people set a writeback percent via sysfs file, /sys/block/bcache<N>/bcache/writeback_percent current code directly sets BCACHE_DEV_WB_RUNNING to dc->disk.flags and schedules kworker dc->writeback_rate_update. If there is no cache set attached to, the writeback kernel thread is not running indeed, running dc->writeback_rate_update does not make sense and may cause NULL pointer deference when reference cache set pointer inside update_writeback_rate(). This patch checks whether the cache set point (dc->disk.c) is NULL in sysfs interface handler, and only set BCACHE_DEV_WB_RUNNING and schedule dc->writeback_rate_update when dc->disk.c is not NULL (it means the cache device is attached to a cache set). This problem might be introduced from initial bcache commit, but commit 3fd47bfe55b0 ("bcache: stop dc->writeback_rate_update properly") changes part of the original code piece, so I add 'Fixes: 3fd47bfe55b0' to indicate from which commit this patch can be applied. Fixes: 3fd47bfe55b0 ("bcache: stop dc->writeback_rate_update properly") Reported-by: Bjørn Forsman <bjorn.forsman@gmail.com> Signed-off-by: Coly Li <colyli@suse.de> Reviewed-by: Bjørn Forsman <bjorn.forsman@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-24bcache: fix inaccurate result of unused bucketsGuoju Fang1-2/+0
To get the amount of unused buckets in sysfs_priority_stats, the code count the buckets which GC_SECTORS_USED is zero. It's correct and should not be overwritten by the count of buckets which prio is zero. Signed-off-by: Guoju Fang <fangguoju@gmail.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09bcache: fix input overflow to cache set sysfs file io_error_halflifeColy Li1-2/+11
Cache set sysfs entry io_error_halflife is used to set c->error_decay. c->error_decay is in type unsigned int, and it is converted by strtoul_or_return(), therefore overflow to c->error_decay is possible for a large input value. This patch fixes the overflow by using strtoul_safe_clamp() to convert input string to an unsigned long value in range [0, UINT_MAX], then divides by 88 and set it to c->error_decay. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09bcache: fix input overflow to cache set io_error_limitColy Li1-2/+1
c->error_limit is in type unsigned int, it is set via cache set sysfs file io_error_limit. Inside the bcache code, input string is converted by strtoul_or_return() and set the converted value to c->error_limit. Because the converted value is unsigned long, and c->error_limit is unsigned int, if the input is large enought, overflow will happen to c->error_limit. This patch uses sysfs_strtoul_clamp() to convert input string, and set the range in [0, UINT_MAX] to avoid the potential overflow. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09bcache: fix input overflow to journal_delay_msColy Li1-1/+3
c->journal_delay_ms is in type unsigned short, it is set via sysfs interface and converted by sysfs_strtoul() from input string to unsigned short value. Therefore overflow to unsigned short might be happen when the converted value exceed USHRT_MAX. e.g. writing 65536 into sysfs file journal_delay_ms, c->journal_delay_ms is set to 0. This patch uses sysfs_strtoul_clamp() to convert the input string and limit value range in [0, USHRT_MAX], to avoid the input overflow. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09bcache: fix input overflow to writeback_rate_minimumColy Li1-1/+3
dc->writeback_rate_minimum is type unsigned integer variable, it is set via sysfs interface, and converte from input string to unsigned integer by d_strtoul_nonzero(). When the converted input value is larger than UINT_MAX, overflow to unsigned integer happens. This patch fixes the overflow by using sysfs_strotoul_clamp() to convert input string and limit the value in range [1, UINT_MAX], then the overflow can be avoided. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09bcache: fix potential div-zero error of writeback_rate_p_term_inverseColy Li1-1/+3
Current code already uses d_strtoul_nonzero() to convert input string to an unsigned integer, to make sure writeback_rate_p_term_inverse won't be zero value. But overflow may happen when converting input string to an unsigned integer value by d_strtoul_nonzero(), then dc->writeback_rate_p_term_inverse can still be set to 0 even if the sysfs file input value is not zero, e.g. 4294967296 (a.k.a UINT_MAX+1). If dc->writeback_rate_p_term_inverse is set to 0, it might cause a dev-zero error in following code from __update_writeback_rate(), int64_t proportional_scaled = div_s64(error, dc->writeback_rate_p_term_inverse); This patch replaces d_strtoul_nonzero() by sysfs_strtoul_clamp() and limit the value range in [1, UINT_MAX]. Then the unsigned integer overflow and dev-zero error can be avoided. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09bcache: fix potential div-zero error of writeback_rate_i_term_inverseColy Li1-1/+3
dc->writeback_rate_i_term_inverse can be set via sysfs interface. It is in type unsigned int, and convert from input string by d_strtoul(). The problem is d_strtoul() does not check valid range of the input, if 4294967296 is written into sysfs file writeback_rate_i_term_inverse, an overflow of unsigned integer will happen and value 0 is set to dc->writeback_rate_i_term_inverse. In writeback.c:__update_writeback_rate(), there are following lines of code, integral_scaled = div_s64(dc->writeback_rate_integral, dc->writeback_rate_i_term_inverse); If dc->writeback_rate_i_term_inverse is set to 0 via sysfs interface, a div-zero error might be triggered in the above code. Therefore we need to add a range limitation in the sysfs interface, this is what this patch does, use sysfs_stroul_clamp() to replace d_strtoul() and restrict the input range in [1, UINT_MAX]. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09bcache: fix input overflow to writeback_delayColy Li1-1/+1
Sysfs file writeback_delay is used to configure dc->writeback_delay which is type unsigned int. But bcache code uses sysfs_strtoul() to convert the input string, therefore it might be overflowed if the input value is too large. E.g. input value is 4294967296 but indeed 0 is set to dc->writeback_delay. This patch uses sysfs_strtoul_clamp() to convert the input string and set the result value range in [0, UINT_MAX] to avoid such unsigned integer overflow. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09bcache: use sysfs_strtoul_bool() to set bit-field variablesColy Li1-8/+8
When setting bcache parameters via sysfs, there are some variables are defined as bit-field value. Current bcache code in sysfs.c uses either d_strtoul() or sysfs_strtoul() to convert the input string to unsigned integer value and set it to the corresponded bit-field value. The problem is, the bit-field value only takes the lowest bit of the converted value. If input is 2, the expected value (like bool value) of the bit-field value should be 1, but indeed it is 0. The following sysfs files for bit-field variables have such problem, bypass_torture_test, for dc->bypass_torture_test writeback_metadata, for dc->writeback_metadata writeback_running, for dc->writeback_running verify, for c->verify key_merging_disabled, for c->key_merging_disabled gc_always_rewrite, for c->gc_always_rewrite btree_shrinker_disabled,for c->shrinker_disabled copy_gc_enabled, for c->copy_gc_enabled This patch uses sysfs_strtoul_bool() to set such bit-field variables, then if the converted value is non-zero, the bit-field variables will be set to 1, like setting a bool value like expensive_debug_checks. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09bcache: fix input overflow to sequential_cutoffColy Li1-1/+3
People may set sequential_cutoff of a cached device via sysfs file, but current code does not check input value overflow. E.g. if value 4294967295 (UINT_MAX) is written to file sequential_cutoff, its value is 4GB, but if 4294967296 (UINT_MAX + 1) is written into, its value will be 0. This is an unexpected behavior. This patch replaces d_strtoi_h() by sysfs_strtoul_clamp() to convert input string to unsigned integer value, and limit its range in [0, UINT_MAX]. Then the input overflow can be fixed. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09bcache: fix input integer overflow of congested thresholdColy Li1-4/+6
Cache set congested threshold values congested_read_threshold_us and congested_write_threshold_us can be set via sysfs interface. These two values are 'unsigned int' type, but sysfs interface uses strtoul to convert input string. So if people input a large number like 9999999999, the value indeed set is 1410065407, which is not expected behavior. This patch replaces sysfs_strtoul() by sysfs_strtoul_clamp() when convert input string to unsigned int value, and set value range in [0, UINT_MAX], to avoid the above integer overflow errors. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09bcache: export backing_dev_uuid via sysfsColy Li1-0/+9
When there are multiple bcache devices, after a reboot the name of bcache devices may change (e.g. current /dev/bcache1 was /dev/bcache0 before reboot). Therefore we need the backing device UUID (sb.uuid) to identify each bcache device. Backing device uuid can be found by program bcache-super-show, but directly exporting backing_dev_uuid by sysfs file /sys/block/bcache<?>/bcache/backing_dev_uuid is a much simpler method. With backing_dev_uuid, and partition uuids from /dev/disk/by-partuuid/, now we can identify each bcache device and its partitions conveniently. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09bcache: export backing_dev_name via sysfsColy Li1-0/+8
This patch export dc->backing_dev_name to sysfs file /sys/block/bcache<?>/bcache/backing_dev_name, then people or user space tools may know the backing device name of this bcache device. Of cause it can be done by parsing sysfs links, but this method can be much simpler to find the link between bcache device and backing device. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-13bcache: set writeback_percent in a flexible rangeColy Li1-1/+2
Because CUTOFF_WRITEBACK is defined as 40, so before the changes of dynamic cutoff writeback values, writeback_percent is limited to [0, CUTOFF_WRITEBACK]. Any value larger than CUTOFF_WRITEBACK will be fixed up to 40. Now cutof writeback limit is a dynamic value bch_cutoff_writeback, so the range of writeback_percent can be a more flexible range as [0, bch_cutoff_writeback]. The flexibility is, it can be expended to a larger or smaller range than [0, 40], depends on how value bch_cutoff_writeback is specified. The default value is still strongly recommended to most of users for most of workloads. But for people who want to do research on bcache writeback perforamnce tuning, they may have chance to specify more flexible writeback_percent in range [0, 70]. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-13bcache: make cutoff_writeback and cutoff_writeback_sync tunableColy Li1-0/+7
Currently the cutoff writeback and cutoff writeback sync thresholds are defined by CUTOFF_WRITEBACK (40) and CUTOFF_WRITEBACK_SYNC (70) as static values. Most of time these they work fine, but when people want to do research on bcache writeback mode performance tuning, there is no chance to modify the soft and hard cutoff writeback values. This patch introduces two module parameters bch_cutoff_writeback_sync and bch_cutoff_writeback which permit people to tune the values when loading bcache.ko. If they are not specified by module loading, current values CUTOFF_WRITEBACK_SYNC and CUTOFF_WRITEBACK will be used as default and nothing changes. When people want to tune this two values, - cutoff_writeback can be set in range [1, 70] - cutoff_writeback_sync can be set in range [1, 90] - cutoff_writeback always <= cutoff_writeback_sync The default values are strongly recommended to most of users for most of workloads. Anyway, if people wants to take their own risk to do research on new writeback cutoff tuning for their own workload, now they can make it. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-13bcache: option to automatically run gc thread after writebackColy Li1-0/+9
The option gc_after_writeback is disabled by default, because garbage collection will discard SSD data which drops cached data. Echo 1 into /sys/fs/bcache/<UUID>/internal/gc_after_writeback will enable this option, which wakes up gc thread when writeback accomplished and all cached data is clean. This option is helpful for people who cares writing performance more. In heavy writing workload, all cached data can be clean only happens when writeback thread cleans all cached data in I/O idle time. In such situation a following gc running may help to shrink bcache B+ tree and discard more clean data, which may be helpful for future writing requests. If you are not sure whether this is helpful for your own workload, please leave it as disabled by default. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-13bcache: introduce force_wake_up_gc()Coly Li1-15/+2
Garbage collection thread starts to work when c->sectors_to_gc is negative value, otherwise nothing will happen even the gc thread is woken up by wake_up_gc(). force_wake_up_gc() sets c->sectors_to_gc to -1 before calling wake_up_gc(), then gc thread may have chance to run if no one else sets c->sectors_to_gc to a positive value before gc_should_run(). This routine can be called where the gc thread is woken up and required to run in force. Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-13bcache: cannot set writeback_running via sysfs if no writeback kthread createdShenghui Wang1-2/+19
"echo 1 > writeback_running" marks writeback_running even if no writeback kthread created as "d_strtoul(writeback_running)" will simply set dc-> writeback_running without checking the existence of dc->writeback_thread. Add check for setting writeback_running via sysfs: if no writeback kthread available, reject setting to 1. v2 -> v3: * Make message on wrong assignment more clear. * Print name of bcache device instead of name of backing device. Signed-off-by: Shenghui Wang <shhuiw@foxmail.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-13bcache: update comment in sysfs.cShenghui Wang1-2/+2
We have struct cached_dev allocated by kzalloc in register_bcache(), which initializes all the fields of cached_dev with 0s. And commit ce4c3e19e520 ("bcache: Replace bch_read_string_list() by __sysfs_match_string()") has remove the string "default". Update the comment. Signed-off-by: Shenghui Wang <shhuiw@foxmail.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>